Egg shells disappear into the dirt in a couple of days. Egg guts mostly sprayed on the visqueen gets rolled up and put in the trash.
And the fun of seeing someone with 9 well splatted eggs from a hundred yards and his reaction when you get down to the backstop and find he creased the egg and it's a leaker. Leakers are egg shooter's version of line cutters.
Or you gets down there and sees a skid mark on the side of the egg but no leak. Yes, you can skid mark an egg with a 22. Been there done that, didn't get the t-shirt.
And you don't get that lovely THAWACK! with anything other than eggs.